3770K Delidded, Lapped, Liquid Pro TIM. What a difference! (Lots of Pics!)

chrisoverson · 14 Jan 2013 at 19:06

Hi guys

. You might have seen my post in which I announced my successful de-lidding of my CPU. I decided I could have done more, so today I took everything apart again and decided to have a go at lapping.

Lid off, TIM removed:

Heatsink marked (badly):

CPU marked:

And away with the lapping... working up from 240 grit.

Went all the way up to 1200 grit, then used some "Lapping Paper" I found at the local tool shop. Don't think that made much difference though.

Lapping the heatsink (a little too much water):

Afterwards, both nice and shiny and down to flat copper:

Liquid Pro on both CPU die and base of IHS:

Liquid Pro on Heatsink:

CPU and IHS in place, more Liquid Pro applied:

.............

Final Results!

Clocked to 4.5ghz @ 1.3vcore

Before (standard IHS TIM, AS5 on heatsink):
Idle temps: 45, 41, 44, 40. Avg = 42.5
Prime95: 85, 90, 90, 84. Avg = 87.25

After 1st De-Lid (Liquid Pro on CPU Die, AS5 on heatsink):
Idle temps: 35, 32, 33, 28. Avg = 32
Prime95: 70, 72, 73, 69. Avg = 71

New result (Lapped, Liquid Pro everywhere

):
Idle temps: 25, 22, 22, 20. Avg = 22.25
Under Load:

56, 56, 57, 53. Avg = 55.5

I think it was worth the few extra hours work

.

This was my first time lapping a heatsink/cpu guys, so I probably did some things wrong. Please share your questions/comments though!

chrisoverson · 14 Jan 2013 at 19:06

Woops, images too big, I'll change them ASAP guys.

chrisoverson · 14 Jan 2013 at 19:19

Okay, fixed the images.

Yes, it did seem like a fair bit of liquid pro, although I must say that stuff goes miles if you take your time with it, I only used the tiniest bead of it to cover both the top of the IHS and the heatsink in one go!

Got the idea to try it from someone in another thread (can't remember who, or I'd have given them credit). But it was quite a thin layer, and it certainly doesn't seem to have hindered performance.

This is all it took for the IHS: Link

chrisoverson · 14 Jan 2013 at 19:28

Litmoose said:
So lapping = sand papering basically? But the difference from the very first test to the end is huge. If it were a f1 car that's like knocking 5 sec a lap off.

Yes, basically sanding it down

.

It seems to have two beneficial effects... one being that you end up with a flatter mating surface for the heatsink and CPU (the CPU is slightly concave as standard, bending inwards at the middle), and the other being the removal of the nickel coating, which doesn't conduct heat as well as copper does.

Using the liquid pro I think definitely helped, as even if I used too much of it it won't hinder performance anywhere near as much as standard paste, because being 100% metal it conducts so much better. It should be as close as I can get to actually soldering the IHS/heatsink on

.

chrisoverson · 14 Jan 2013 at 19:36

If you're into F1 btw one of the things I often use this PC for is F1 2012, if you want to come play

.

I'll be benchmarking that later, after I try to push the CPU frequency up again. (GPU will probably be the bottleneck but still fun to try).

chrisoverson · 14 Jan 2013 at 20:29

Winston said:
Makes me want to redo mine with liquid pro and get the sandpaper out!
Nice results

Thanks

.

Be sure to post up the results if you do, I'm quite surprised how much difference it's made.

Now running 4.7ghz @ 1.36vcore, max temps under Prime95 got to 67.25 average. Much better than before; I couldn't even get 4.7ghz without 1.42v.

chrisoverson · 14 Jan 2013 at 23:45

I did... I originally was doing it on an old side from a case, but it kept moving so I gave in and did it directly on the desk.

I know that if I'd done it on a perfectly flat metal surface it might have been better... but I had nothing of the sort to hand. Hasn't damaged the desk, and seems to have worked well

.

chrisoverson · 15 Jan 2013 at 23:21

Nickolp1974 said:
i'd suggest maybe a piece of glass next time did mine on an old glass hifi stand!

I hunted everywhere for a spare bit of glass... didn't have one to hand.

I've got an old dead printer/scanner though, I'll probably take the glass plate out of that for next time

chrisoverson · 16 Jan 2013 at 12:12

I think one of the big issues with these chips is how varied the results are.

I've seen some people getting 4.5ghz on silly low voltages, others need 1.3v or higher. The inconsistancy is just crazy.

It stands to reason that because the chips aren't soldered, but are just slathered in crappy intel TIM, that that process isn't always equal also... so some people will benefit far more from delidding than others. Also, there's difference in motherboards, ambient temperatures etc.

As for lapping, because heatsinks aren't always flat, and the IHS isn't always flat, and it seems that some are shaped differently (some concave, some convex, some flat to start with), then different people with different heatsinks will have different experiences with lapping.

Also, the more you take off the IHS and heatsink the closer you get to contact between the die and heat pipes... so thats a factor too. If you spent longer with lower grit sandpaper and took more of the IHS away... then perhaps it conducts heat better? It's not really a precise art.

I'm currently writing this on my laptop because I'm playing with voltages etc. on my PC. If you're not believing some of the results I'm getting... then by all means I'll do further testing and show some more evidence.

chrisoverson · 16 Jan 2013 at 15:07

Okay, just done some more testing. Got the core voltage down to around 1.25v now for 4.5ghz.

Max temps in CoreTemp after running Prime95, Intel Burn Test, 3DMark11 (Extreme) and my own Lottery Simulator benchmark which I've been making in C#:

56, 56, 58, 52. Avg = 55.5. Pretty much exactly the same as 2 days ago.

Screenshot: Link

Sorry for the high res - it includes all 4 screens.

Also done 4 consecutive benchmarks in F1 2012... so it seems fairly stable all in all at these settings.

chrisoverson · 16 Jan 2013 at 20:43

Thanks guys

Well, the lapping itself took perhaps 3 hours or so... but it's hard to say as I left part way through to see a customer and get some finer sandpaper.

It didn't feel like it took long, but all told I spent most of the day tinkering.

I was surprised about the Liquid Pro TIM though, I thought it would stick but when I opened the clamp the IHS literally fell off the CPU (the computer was half standing up at the time). Anything left was easily removed.

I'm not sure about the difference between Liquid Pro and Ultra... but I do remember seeing that the thermal conductive rating is different. Also the ultra is more of a paste I think, whilst the pro stuff looks like liquid solder, and is a bit tricky to spread.

I would say if you're looking into doing this and your temps are too high, then definately go for it if you think you have the motor skills, patience and are brave enough. It really isn't all that hard to do, as long as you are careful when getting the blade under the IHS to begin with. After that, I would DEFINATELY recommend using plastic to complete the process. Far far safer and very easy. Also remember to keep the blade flat, and only use a rigid non flexible blade (I used a stanley blade). I tried blunting one first, but I couldn't get it under the IHS, so it has to be sharp.

chrisoverson · 16 Jan 2013 at 20:47

If you are going to do this... I would recommend not bothering to lap the CPU/heatsink until you've had it working for a little while after delidding and changing the TIM. If it turns out you have any problems, then you might be able to still re-glue the IHS and send it back under warranty, before you permanently alter your chip.